The main problem in processing manufacturing resins is to control the temperature of the processing container, especially in the case of strong exothermic reactions present in processing P/F resin. In the case of processing resin, for example, in the past the prior art has not always had sufficient cooling capacity in their condensers to control the exothermic portion of the reaction. This has led in extreme cases to atmospheric venting of the kettle contents. Because of this, a high cooling capacity is necessary to produce the resin in a safe and economic manner. The problem is solved by recognition of important considerations of the system design so it can be balanced, along with a change in the operation of the process and a new solution for handling the problem of entrainment. For the production of resin, the pre-resinous solution must be pre-heated to a certain temperature where the exotherm reaction can start efficiently. The batchcook has to follow a time-temperature-profile. During the production of resin, the condenser system is needed
to keep a certain temperature in the kettle and to remove the exotherm heat PA1 to cooldown the batch to a certain temperature or to the lowest temperature at the final cooldown, as fast as possible PA1 to catch an out-of-control reaction created by a strong exotherm reaction (exotherm heat increases exponentially with temperature)
The batchcook is cooled by means of a vacuum system which decreases the pressure in the kettle to the boiling-point temperature (temperature-pressure boiling-point curve for water) and creates the pressure-difference which pulls vapor and an unknown amount of liquid resin (Entrainment) through a vapor recovery line and into a condenser. The vapor is then transported through a condenser in which the vapor collapses to liquid. These tubes are surrounded by coolant, such as water, which circulates through the condenser. As a result, the latent heat (resulting from changing vapor to liquid) and heat from additional subcooling of the liquid is transferred to the circulating water (in the cooling water system) and removed from the condenser system and accordingly from the kettle. The condensated liquid is then returned by means of a reflux line to the kettle.
In existing condenser systems, liquid resin particles, hereinafter referred to as liquid, particles, droplets or resin, Entrainment, which is pulled from the surface of the batchcook by the vapor velocity accelerating at the batch surface, accumulates on the walls of the condenser tubes. This resinous coating reduces the heat transfer-coefficient from the collapsing vapor to the circulating water (cooling-water system) in the condenser. This reduction of the efficiency of heat transfer increases the amount of time and cost required to cool the batchcook. As a consequence of the resin build-up, which is known as fouling, frequent cleaning of the condenser system is required.
Also, in the prior art, the operation of the system is controlled by observing the liquid level in a sight glass in the reflux line to control system operation. The prior art did not control system operation as a function of the pressure-difference in the system. The present invention includes installation of two pressure-transmitters to determine system pressure difference between the kettle pressure and the vacuum source 12, as well as absolute pressure at the kettle. The system is then controlled by reference to the pressure-difference which is considered to be the driving force for the kinetic energy which results in the mass flow and cooling rate.